The lowest molding which projects at the base of a column
and above the plinth.

Etymology: Latin: a bulge, swelling

Resembles a semicircle.

In Egyptian temple architecture, the
cavetto cornice generally
had a torus beneath, as in the left illustration above..

The earliest examples are found in Egypt, where it was carried up the angles of the pylon and temple walls and horizontally across the same.

Its most frequent employment is in the bases of columns;
in the Roman Doric order being the lowest moulding; in the Ionic orders there are generally two torus mouldings separated by a scotia
[a deep concave molding between two fillets] with fillets [a narrow part of the surface
of a column between adjoining flutes].

Both in Greek and Roman bases sometimes the torus is elaborately
carved .